1. Field of the Invention
This invention relates to implants having electrodes and/or contacts for conducting electrical signals and/or delivering energy directly to one or more parts of a patient's body.
2. Related Art
The following publications are referred to in the present application and their contents are hereby incorporated by reference in their entirety: “Multifunctional Carbon Nanotube Yarns by Downsizing an Ancient Technology”, Science Vol. 306. no. 5700, pp. 1358-1361; “Strong, Transparent, Multifunctional, Carbon Nanotube Sheets”, Science Vol. 309. no. 5738, pp. 1215-1219); International Patent Application No. PCT/AU99/00391 (WO 00/71063 to Cochlear Limited); and U.S. Pat. No. 7,240,416 to Cochlear Limited.
Medical implants are used in many areas of medicine to enhance the length and/or quality of the life of the implant recipient. Such implants include pacemakers, controlled drug delivery implants and cochlear implants.
A cochlear implant allows for electrical stimulating signals to be applied directly to the auditory nerve fibers of the patient, allowing the brain to perceive a hearing sensation approximating the natural hearing sensation. These stimulating signals are applied by an electrode array implanted into the patient's cochlea.
The electrode array is connected to a stimulator unit which generates the electrical signals for delivery to the electrode array. The stimulator unit in turn is operationally connected to a signal processing unit which also contains a microphone for receiving audio signals from the environment, and for processing these signals to generate control signals for the stimulator.
The signal processing unit is in practice, located externally to the patient and the stimulator is implanted within the patient, usually near the mastoid on the patient's skull and underneath the surrounding tissue. The processor and stimulator may communicate by various wireless means including by a radio frequency link.
During insertion of the electrode, damage to the delicate structures of the patient's cochlea often occurs. This damage may cause a loss of any residual hearing.
Several methods have been proposed to reduce insertion trauma, including pre-curved electrode arrays and the use of insertion tools. However, these have not been particularly successful.